Heretofore, there has been an image forming apparatus of a process cartridge type in which a cartridge such as a drum cartridge provided with a photosensitive drum or a developing cartridge provided with a developing roller. For example, in U.S. Pat. No. 7,813,670, a door provided to an apparatus main assembly is opened and then the cartridge can be demounted. Further, the door is provided with a positioning urging portion for urging the cartridge in a closed state to position the cartridge in the apparatus main assembly. Such an image forming apparatus is capable of individually replacing (exchanging) the photosensitive drum and the developing roller and therefore is effective in such a case where a product lifetime is different between the photosensitive drum and the developing roller.
However, with downsizing of the image forming apparatus in recent years, there arises a need to suppress a height of the apparatus main assembly or a size of the image forming apparatus with respect to a widthwise direction. With the need, a path along which the cartridge is demounted from the apparatus main assembly is being narrowed.
In the U.S. Pat. No. 7,813,670, the cartridge demounting path become narrow with the downsizing of the apparatus, so that when the cartridge was demounted, the cartridge contacted the positioning urging portion of the door and thus there was a possibility that damage or breakage of the positioning urging portion was caused.